The comptroller of Dixon, Illinois, recently pleaded not guilty to a charge that she had embezzled more than $53 million in public funds over more than two decades.

Rita Crundwell's alleged misappropriation was uncovered earlier this year by a fellow city employee who temporarily took charge of her duties while she was on a leave of absence.

The Rockford Register Star reports that she was able to keep the embezzlement hidden despite numerous accounts payable audits and recovery audits because she was the only person who paid bills and had access to the city's bank accounts, receiving little – if any – oversight from colleagues or elected officials.

"There were no red flags," said Brad Hahn, communications director for the state comptroller, as quoted by the news source.

The fact that Crundwell's duties were not adequately segregated likely facilitated the embezzlement, as she was allowed to write and sign checks, then balance the city's books at the end of each month.

"When you have that all commingled, it does make it a little bit more easy to have (fraud) happen," Carol Jessup, an accounting professor at the University of Illinois Springfield, told the State Journal-Register.